Eisai obesity drug Belviq may have an edge with new heart-safety data—but to what end?

Eisai last year bought Belviq from creator and marketing partner Arena. (Eisai)

More than six years after winning approval, obesity drug Belviq has shown it’s heart-safe. But whether that claim can jump-start sales in an ice-cold market remains to be seen.

In a 12,000-patient cardiovascular outcomes study—the largest to date for a weight-loss drug, owner Eisai said—Belviq showed it didn’t increase the combined incidence of heart attack, stroke and CV death in obese patients.

And while it didn’t prove superior to placebo in preventing those events plus a handful of others, it showed it was non-inferior in that department, too.

The results make Belviq the first and only product approved for chronic weight management to demonstrate heart safety in an outcomes trial, despite the fact that outcomes trials are part of the FDA's postmarketing requirement for obesity drugmakers. And that means Eisai will be the only maker of obesity drugs able to talk up heart safety as a competitive edge.

It also means Eisai is the only obesity drugmaker that no longer has to worry a failed outcomes study could compromise its drug's approval status.

So why haven’t Belviq’s rivals, Vivus’ Qsymia and Nalpropion’s Contrave, gone through trials of their own? It’s simple: Money. Over the last five years, obesity drugs have failed to gain traction, leaving their makers empty-handed when it comes to funding studies with estimated costs of about $200 million.

It wasn’t always that way—at least with Contrave. Creator Orexigen, which agreed to sell Contrave to Pernix-owned Nalpropion in April, started two outcomes studies, only to end up nixing both. The first time around, it disclosed data on the still-in-progress trial, spoiling the study and seriously denting a relationship with copromoter Takeda. The Japanese drugmaker eventually walked, and Orexigen scrapped a second study in favor of soldiering on without its partner.

Vivus, though—whose decision to market Qsymia without a Big Pharma partner spurred a proxy brawl in 2013—just hasn’t had the cash. Through multiple rounds of layoffs, it’s promised investors it would work with the FDA to scale down the study requirements, and it’s already held “several meetings” with the agency to “discuss alternative stragies … for obtaining outcomes data,” it said in a May financial filing. So far, though, those haven’t amounted to much—and even if the FDA “were to determine that a CVOT is no longer necessary, there would be no assurance that the EMA would reach the same conclusion,” Vivus cautioned in the same filing.

Belviq’s maker Arena, meanwhile, went running for the exits early last year, handing off the product to marketing partner Eisai for $23 million in cash payments, as well as what it estimated would be more than $80 million in cost savings. But the drug hasn't exactly soared since then; it brought in just $3.6 million in Eisai's fiscal 2017, which ended this March.

Stiffer competition could be on the way from Novo Nordisk, too. The Danish drugmaker is doubling down on a largely untapped obesity market, and it has the funds to do it. In November, it said it would seek approvals for already marketed Saxenda in additional countries, and it’s developing GLP-1 drug semaglutide for weight loss, too.